How are PID algorithm and robot control system united in wedlock?

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Introduction: Generally speaking, the robot divides composition by a few greater part, it is mechanical part respectively (it is to show through each joint is linked together commonly mechanical arm of composition) , send feeling share (the measurement unit that includes to measure the position, speed to wait) , and control part (undertake handling to passing what move part transmits to measure signal and give out to control function accordingly) . The robot learned to represent current and compositive degree tall, have representative hi-tech field, it is integrated much door course. Include the across of the much discipline such as engineering of mechanical engineering, computer technology, control, electronics, biology and confluence among them, reflected the advanced level of current and practical science and technology. Generally speaking, the robot divides composition by a few greater part, it is mechanical part respectively (it is to show through each joint is linked together commonly mechanical arm of composition) , send feeling share (the measurement unit that includes to measure the position, speed to wait) , and control part (undertake handling to passing what move part transmits to measure signal and give out to control function accordingly) . Those who serve as a robot " cerebrum " , the importance of robot control technology is self-evident it basically is the information that conveys through sending the share such as feeling, use control algorithm, make the share that mechanical part finishs a target to operate and assumes correspondence of corresponding control function. Ultimate goal is to reduce a robot as far as possible the deviation of virtual campaign contrail and expectation target, achieve ideal athletic precision. Robot controller is system of control of a computer, it controls a technology to be theory with the robot, what cooperate a robot even at the same time is kinematic and kinetic build a model. At this moment, we change the physical model of a complex, abstraction into the opposite clarity, maths model that provides an elephant, once build, so we go up to come out control problem from the depart in particular robot device in certain level, undertake to its further ground is known thereby. As the robot the gradual progress of relevant science and technology, control algorithm also becomes rich gradually rise, produced such as from adaptive control, control from corrective control, rash club, become structural control, nonlinear systematic control, forecast the strategy of numerous and new-style control such as control. But, in numerous and outstanding control algorithm, most active should belong to PID (scale, integral, differential) control, also the development on the foundation that is based on PID to control algorithm comes out a lot of advanced control strategy. In producing process system pilot to develop course, PID control is the history one of main control pattern with the longest the strongest vitality. It is OK below the simplest case that in 20 centuries 40 times are divided before outside using switch control, it is only control way. 20 centuries, communication technology, electron technology begins to develop. At the same time war, industry also became impetus, automata technology and automata theory begin rapid development. The absurd source of student of PID at the human relevant research to feedback system. 20 centuries 20 time, the scientist of lab of phone of American shellfish Er this work up the frequency character of feedback control system analyses a method. Shellfish Er lab has the engineers of communication setting to often be familiar with frequency domain method very much. 1932, nai Kui this special (H · Nyquist) publish a paper, the method that uses a figure will judge systematic stability. This covers a method, also use at the analysis of automation system and design later. Later, feedback controls a principle to begin to apply at industrial procedure. The hertz Ceng Jiao that manage of American hemp province was versed in 1934 founded servo control is academic, put forward orbit to dog to control medium value in feedback first. After two years, of England take an examination of Lun De (A · Callender) with Sidiwensen (A · Stevenson) waited for a person to give out the method of PID controller. Say simply, PID pilot advantage has 3: The technology is mature, control effect is admirable; Adaptability is strong, control a target to all sorts of processes, PID algorithm accords with a requirement almost; Rash club sex is strong. Among them, rash club sex (Robustness) point to, it mirrors feedback to control a system to have bear the ability that this kind of uncertainty affects. Simple for, better when rash club sex when showing the certain physics character when the robot produces change namely, PID algorithm still can be the attitude control of the robot inside reasonable range. On one hand, PID cost is low, operate easily; On the other hand, the majority controls an object to be able to use PID control directly, and need not get to the bottom of its model mechanism, because of its more powerful rash club the gender can make sure function index of the system satisfies basic requirement. On common sense, PID controller is linear controller. PID pilot meaning is, after the error signal that after feedbacking the course, gets has scale P, integral I and differential D operation respectively again overlay gets controller outputs signal. In real work process, the system gives out set-point (also can call expectation to be worth) , measure link to measure the actual output that give to be worth feedback to give a system, and will produce deviation E with expectation value. And the action of PID controller corrects this deviation E namely. When specific applying, we but specific issue is specific analysis, choose the combination with P, PI, PD, different PID according to real need. In actual unit process of cargo bandling, the controls a system to debug a process key of the robot depends on adjusting scale, integral, differential the coefficient of these 3 link. Had algorithm, how should be united in wedlock with the robot? We lift an exemple to explain. We with annulus type robot is exemple, walk steadily to make a robot OK, we need electric machinery of noumenal to drive robot servo to undertake controlling, the PID that needs pair of servo driver itself above all so undertakes modulatory. Next, to dominate the result more accurate, the system still can use controller of motion of open mode much axis (PMAC) , and this control card also can undertake PID adjustment, the control system of this kind of robot can simplify flow. So, are these 3 link in this scale, integral, differential what kind of effect to have after all in robot system? 3 link have each distinguishing feature each, let me look respectively: Scale P: It can mirror a robot " current " the deviation between advancing speed and control personnel set-point, KP is bigger, what the system adjusts is faster, but too big later can bring about a robot to move to be not stabilized; Integral I: It can mirror a robot " accumulative total " deviation, want to have an error only, integral link can adjust, final meeting is adjusted make the system does not have deviation, although get a robot to achieve the athletic status that operation personnel gives out; Differential D: It is OK " ahead of schedule " foreknow the trend of robot motion deviation, having notting forming previously, lead ground eliminates an error; In 3 link, integral I link and differential D link cannot be used alone, must combine scale P link to use ability to go together. In this system, hold accuse personnel to undertake through computer and robot interactive, give out to control an instruction accordingly (stop for instance, advancement) , the PID of servo drive has initial control to servo electric machinery, the measurement of servo electric machinery signal feedback gives open mode controller of much axis motion, next the PID of this controller can undertake to the system again thin tone, make servo electric machinery moves more smoothly, finish control personnel to be opposite thereby all sorts of operation instructions of round of type robot. Since the computer enters control field, replace analog computer adjuster to form control system with the digital computer. For convenient computer computation, PID still can use increment type expression. To mechanical component, such doing have profit greatly, the computer outputs control increment only every time can, make the impact when reducing robot breakdown to happen so, can realize the switch that do not have faze, at the same time PID control also becomes more agile. CNC Milling CNC Machining